Table 3.
FIC index of nanoparticles in combination with antimicrobial agents against Pseudomonas aeruginosa Xen 5
| Tested antibiotics | FIC index |
P. aeruginosa Xen 5
|
Interpretation – 1/2/3 | ||
|---|---|---|---|---|---|
| Combination with
| |||||
| 1 – MNP@NH2 | 2 – MNP@Au | 3 – MNP@PQAS | |||
| LL-37 | FIC index | 0.5 | 0.14 | 2 | PS/S/I |
| CSA-13 | FIC index | 0.13 | 0.375 | 1 | S/S/AD |
| CSA-131 | FIC index | 0.53 | 1 | 1 | PS/AD/AD |
| COL | FIC index | 1 | 1 | 0.5 | AD/AD/PS |
Notes: FIC values >4 indicate antagonistic effects (AN), values between 4 and 1.01 indicate indifference (I), values between 1 and 0.76 indicate additive effects (AD), and values <0.76–0.5 indicate partial synergy (PS) and <0.5 indicate a synergistic effect (S).
Abbreviations: FIC, fractional inhibitory concentration; MNP, magnetic nanoparticle; PQAS, poly(quaternary ammonium salts); CSA, cationic steroid antibiotic; COL, colistin; LL-37, cathelicidine LL-37.